I can only assume that Dr Germany has a prejudicial interest in making such announcements - I don't know anyone who's flown rotary for more than 2000 hrs who does not suffer from some sort of back discomfort
Personally, I would not consider getting airborne without a lumbar cushion strapped to the seat, and remembering to shove my ar*e firmly into the crook of the seat, both when stapping in and on a regular basis during longer flights. Despite better seat design nowadays, the back cushion lumbar area never seems to take long to soften &/or flatten, thus negating its lumbar support properties.
I was also encouraged (in my earlier days) to ensure that lap straps were tight enough to keep the bum to the back of the seat, but not too tight to numb the legs!
Other than the above, as others have said, it's a known occupational hazard - all you can do is minimise it by following some of the tips
!